I received two APM/IMU sets and one seems to have a problem. The sensor readings are jumping all over the place.
This is the sensor readings of the board sitting on stable flat surface.
What options are there to diagnose this or do I send it back to the store?
Did you solder the APM/IMU connectors yourself or did they come pre-soldered? If you did them yourself, you might start looking at your connector solder joints to ensure that they are shiny and clean. Sounds like a connector/solder problem to me.
Just a thought.
I've been following your problem (sorry ur having a difficult time) but I can't help wondering if you have a power problem. The erratic behavior on two different sets of H/W plus the problem with your connectivity. So how are you powering your quad. Have you tested the quality of your power subsystem?
That is something I didn't think to check but I'm powering it with this castle BEC. I connect it to the far left set of pins and then I have 3 wire servo cables going from the APM to the receiver.
But in most of the recent testing, to isolate things, I'm just powering it via USB with nothing at all connected to the triple row pins.
Powering from the USB might not be enough. See what happens if you power it from a LiPo. Also, you might think about not connecting the power pins (middle pin in the 3 row) from the receiver. Try a different BEC connection as well. What is the power rating of the BEC.
Why not connect the power pin on the triple row? I thought all power and ground pins on receiver were all connected. Should I run a ± cable from APM to receiver? I thought having all 6 servo cables connect to ground and positive would be better in case there was a bad connection. The power rating of the BEC is 10A.
Actually that is how I power my larger quad which doesn't have any problems. For this mini quad I connected only the signal wires from the APM to the receiver. Then I have a 3 wire cable going from far left triple pin on APM to battery connection on AR6110e receiver. Then to power everything I left one ESC with it's power cable connected and the other 3 ESCs I cut the red wire. Do you think this Plush-6A Turnigy is not sufficient to power APM/IMU?
I really prefer to use BECs always but for this miniquad I was trying to keep everything minimal. I also thought the USB connection would be enough power for it to function propery. I'm using a macbookpro17. I will try a BEC connection and see if the gyros calm down :)
USB delivers enough power (for apm, not reciever, xbee or something but this works in most cases, too)
turnigy plush 6A delivers enough power (i had it like this on my quad, switched over to the APMs build in voltage regulator)
it's not a power issue, and no APM - IMU connection problem (ADC is connected via SPI, if one connection fails you would get no data, not even wrong data)